Fortinet FortiOS < 5.2 / 5.4.x < 5.4.6 / 5.6.x < 5.6.1 SSL / TLS Renegotiation Handshakes MitM Plaintext Data Injection (FG-IR-17-137)

Medium Nessus Plugin ID 104656


The remote host is affected by a MITM vulnerability.


The version of Fortinet FortiOS running on the remote device is 5.2.x or prior, 5.4.x prior to 5.4.6, or 5.6.x prior to 5.6.1. It is, therefore, affected by a MITM vulnerability in SSL Deep-Inspection due to insecure TLS renegotiation.


Upgrade to Fortinet FortiOS version 5.4.6 / 5.6.1 or later.

See Also

Plugin Details

Severity: Medium

ID: 104656

File Name: fortios_FG-IR-17-137.nasl

Version: $Revision: 1.2 $

Type: local

Family: Firewalls

Published: 2017/11/17

Modified: 2017/11/20

Dependencies: 73522

Risk Information

Risk Factor: Medium


Base Score: 4

Temporal Score: 3

Vector: CVSS2#AV:N/AC:H/Au:N/C:P/I:P/A:N

Temporal Vector: CVSS2#E:U/RL:OF/RC:C


Base Score: 7.4

Temporal Score: 6.4

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:fortinet:fortios

Required KB Items: Host/Fortigate/model, Host/Fortigate/version

Exploit Available: false

Exploit Ease: No known exploits are available

Patch Publication Date: 2017/11/03

Vulnerability Publication Date: 2017/11/03

Reference Information

CVE: CVE-2009-3555

BID: 36935

OSVDB: 168749

CWE: 310